Modular shaft assembly

ABSTRACT

The invention relates to a modular shaft assembly for a media dispenser comprising a common shaft and a drive shaft. The common shaft comprises a central portion between two end portions. Each end portion has a pulley-mounting region and at least one end portion has an aperture in the end of the common shaft, co-axial to the common shaft, for receiving a connecting portion of the drive shaft. The drive shaft comprises a central portion between a connecting portion and a drive portion. The connecting portion is arranged to connect the drive shaft co-axially to the common shaft by insertion of the connecting portion into the aperture in an end portion of the common shaft. The drive portion comprises a gear-mounting region.

The present invention relates to a modular shaft assembly for carrying pulleys and/or gear wheels. It is particularly related to, but in no way limited to, shafts for use in media handling in an automated teller machine (ATM).

BACKGROUND OF THE INVENTION

A cash dispenser unit of an automated teller machine (ATM) uses pulleys to handle media. In some cases the media may be handled directly by the pulleys and in other cases the pulleys may be used to drive and tension belts which handle the media. These pulleys are mounted on shafts. The use of such shafts and pulleys can be described with reference to FIG. 1 that shows a schematic side elevation view of a cash dispenser unit 73 of an ATM.

The cash dispenser unit 73 holds a number of currency cassettes 89 each holding a stack of currency notes 68. When one or more notes are to be dispensed from a particular cassette, the pick mechanism 74 associated with the cassette draws a note from the cassette such that its leading edge is gripped between pulleys (or rollers) 90. The note is then fed along the feed path 72 by further pulleys 92 and by belts 93 carried by pulleys 92′. The note passes through a retard mechanism 10, comprising an arrangement of pulleys 11 and belts 12, to a stacker wheel assembly 75. In operation, the stacker wheel assembly 75 rotates continuously in a counter-clockwise direction (for the arrangement shown in FIG. 1) and the note is fed into a compartment 81 formed between adjacent tines 78. If more than one note is to be dispensed, each note is fed into a successive compartment 81 as the stacker wheel assembly 75 rotates. Having completed half a rotation, the note is removed from the stacker wheel assembly 75 by fingers 94 of a stripper plate assembly 96 pivotally mounted on a shaft 98. Once removed from the stacker wheel, the note is placed on a belt 100 resting against the stripper plate assembly 96 and any subsequent notes which are to be dispensed simultaneously with the first note are placed on top of the first note to form a bundle 68′. When the required amount of notes (which may be just one note) have been assembled into the bundle 68′, a pair of belts 102 (only one of which is shown in FIG. 1) is rotated on a shaft 104 such that the bundle 68′ is trapped between the belts 100,102. The bundle is then fed between belts 100, 102, 106,108 through a note exit slot 110 in the housing 112 of the cash dispenser unit 73 to a position where the bundle 68′ can be collected by the user of the ATM. The belts 100, 102, 106, 108 are all carried by pulleys mounted on shafts. If a multiple feeding is detected in the course of stacking the bundle of notes 68′ or one or more of the notes is rejected for any reason, the bundle is not fed to the note exit slot 110. Instead the stripper plate assembly 96 is pivoted into a position as shown by the dashed outline 96′ and the belts 100, 102 are operated in the reverse direction to deposit the bundle 68′ into a reject note container 114 via an opening 116.

Each of the pulleys 11, 90, 92, 92′ shown in FIG. 1 are mounted on shafts (not shown). The pulleys may be drive pulleys, which are connected to shafts rotated by a motor, or may be idler pulleys, which are mounted on shafts which are not driven and are used to tension belts. Typically a belt 93 would be carried by one drive pulley and one or more idler pulleys.

FIG. 2 shows a schematic diagram of the mounting of the shafts and pulleys within the dispenser unit of an ATM. The steel shafts 201, 202 are mounted parallel to each other in a supporting steel framework having parallel side walls 203, 204. Typically each shaft is 300 mm long. Each shaft extends beyond the side walls of the steel framework and is able to rotate about its longitudinal axis due to large bearings. Two pulleys are mounted on each shaft, with the pulleys 205, 206 on the first shaft 201 being aligned with the pulleys 207, 208 on the second shaft 202. Each pulley carries a belt 209-212 that is tensioned by one or more idler pulleys mounted on further parallel shafts, not shown in FIG. 2. The shafts 201, 202 are connected at one end by gears 213 to a motor 214 that drives the shafts and hence causes the belts to rotate. Media 215 can be transported between pairs of aligned belts (two pairs shown in FIG. 2: 209, 211 and 210, 212).

The design of the dispenser unit as described above makes it hard to service the equipment or to extract media that may have become trapped in the feed path. In order to access the pulleys, belts and any trapped media it is necessary to remove the dispenser unit from the ATM (which means removing it from the safe) and disassemble the supporting steel framework.

SUMMARY OF THE INVENTION

The invention seeks to provide a modular shaft assembly that mitigates problems of known shafts and enables the dispenser unit to be more easily serviced and repaired.

This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

A first aspect provides a modular shaft assembly for a media dispenser comprising a common shaft and a drive shaft, wherein the common shaft comprises: a central portion between two end portions, each end portion comprising a pulley-mounting region and at least one end portion comprising an aperture in the end of the common shaft, co-axial to the common shaft, for receiving a connecting portion of the drive shaft, and wherein the drive shaft comprises: a central portion between a connecting portion and a drive portion, wherein the connecting portion is arranged to connect the drive shaft co-axially to the common shaft by insertion of the connecting portion into the aperture in an end portion of the common shaft, and the drive portion comprises a gear-mounting region.

Advantageously, as a result the shaft assembly being modular, a dispenser unit containing such a shaft can be more easily serviced and repaired.

A further advantage is that the common shaft can be used in several different places and only the length of the drive shaft varied.

A further advantage is that the forces on the pulleys are applied close to the bearings that support the common shaft. This reduces the stresses on the common shaft.

Preferably each end portion comprises an aperture in the end of the common shaft, co-axial to the common shaft, for receiving a connecting portion of the drive shaft.

Advantageously, the common shaft can be used in either orientation and it is not necessary to check orientation in assembly, installation or repair.

Further advantageously, drive shaft can be connected to more than one common shaft using a connecting element inserted into the apertures in the ends of the common shafts.

Preferably the central portions of the common shaft and the drive shaft have a cruciform cross-section.

Advantageously, this provides a structure that is easy to manufacture and is also robust and rigid.

Preferably each end portion of the common shaft further comprises: a flange between the central portion and the pulley-mounting region; and a bearing-mounting region adjacent to the pulley-mounting region.

Preferably the drive portion of the drive shaft further comprises: a bearing-mounting region between the gear-mounting region and the central portion.

Preferably the apertures in the end portions of the common shaft and the connecting portion of the drive shaft have a polygonal cross-section.

Preferably the apertures in the end portions of the common shaft and the connecting portion of the drive shaft have a hexagonal cross-section.

Preferably each of the common shaft and the drive shaft are integrally molded and further preferably they are integrally molded from a thermoplastic polyester.

Preferably the pulley-mounting regions of the common shaft comprise raised features arranged to prevent a pulley mounted on the shaft from rotating on the shaft.

Preferably the common shaft is 90 mm long and has a diameter of 6mm.

Preferably the aperture is 3-15 mm deep.

A second aspect provides a media dispenser comprising a modular shaft assembly as described above.

Preferably, the media dispenser further comprises one or more additional common shafts.

A third aspect provides a common shaft substantially as described with reference to FIGS. 3-8 of the drawings.

A fourth aspect provides a drive shaft substantially as described with reference to FIGS. 9-12 of the drawings.

A fifth aspect provides a modular shaft assembly substantially as described with reference to FIG. 13 of the drawings.

The preferred features may be combined as appropriate, as would be apparent to a skilled person, and may be combined with any of the aspects of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention will be apparent from the following specific description, given by way of example, with reference to the accompanying drawings, in which

FIG. 1 is a schematic side elevation view of a cash dispenser unit;

FIG. 2 is a schematic diagram of the mounting of shafts and pulleys within the dispenser unit of an ATM;

FIG. 3 is a schematic diagram of a common shaft;

FIG. 4 shows a cross-section through the central portion of the shaft shown in FIG. 3;

FIG. 5 shows a cross-section through an end portion of the shaft shown in FIG. 3;

FIG. 6 shows a cross-section through a pulley suitable for mounting on the shaft shown in FIG. 3;

FIG. 7 shows a cross-section of the aperture in the end of the shaft shown in FIG. 3;

FIG. 8 is a schematic diagram of the shaft of FIG. 3 once pulleys, bearings and belts have been mounted;

FIG. 9 is a schematic diagram of a drive shaft;

FIG. 10 shows a cross-section through the connecting portion of the shaft shown in FIG. 9

FIG. 11 shows the gear-mounting portion of the drive shaft in more detail;

FIG. 12 shows a cross-section through the gear-mounting portion, with the gear mounted on the drive shaft; and

FIG. 13 is a schematic diagram of a common shaft connected to a drive shaft.

Common reference numerals are used throughout the figures to indicate similar features.

DETAILED DESCRIPTION

FIGS. 3-8 are schematic diagrams of a shaft which is modular, in that it can be connected to other shafts, such as a drive shaft as described below with reference to FIGS. 9-13. It is referred to herein as a ‘common shaft’ because it can be used both for driven pulleys when connected to a drive shaft, and for idler pulleys when used without being connected to a drive shaft.

The common shaft 300 comprises three sections, a central section 301 and two end sections 302. The central section 301 has a cruciform cross-section as shown in FIG. 4. This is beneficial because it provides a robust and rigid shaft whilst reducing the cross-sectional area, which makes the shaft easier to manufacture, particularly when formed by molding. Each end section is identical which means that on installation or repair it is not necessary to check the orientation of the shaft. Each end section comprises a flange 303 adjacent to the central section 301. This flange is used to control the position of both a pulley mounted on the shaft and also a belt carried by the pulley (see FIG. 8). Adjacent to the flange is a pulley-mounting region 304. This region is substantially circular in cross-section (see FIG. 5), but with the addition of raised features 305 (e.g. two parallel ridges). Pulleys 600 to be mounted on the shaft are provided with a corresponding aperture 601 (e.g. with two corresponding parallel grooves, see FIG. 6), such that pulleys mounted on the shaft are prevented from rotating freely. Adjacent to the pulley-mounting region and at the end of the shaft is a region with substantially circular cross-section 306 where a bearing can be mounted. A suitable known bearing comprises a steel inner hoop and a steel outer hoop separated by ball-bearings. The end of the shaft 307 is perpendicular to the longitudinal axis of the shaft. In the end of the shaft is an aperture 308 (shown in FIG. 7 and indicated by the dotted line in FIG. 3) for connecting the shaft 300 to another shaft, such as a drive shaft. The aperture is co-axial with the longitudinal axis of the shaft. The aperture has a substantially polygonal cross-section, (e.g. hexagonal as in the example shown), such that another shaft having a portion with an external shape of a similar polygonal cross-section can be inserted into the aperture and when one shaft is rotated, both shafts rotate together (as shown in FIG. 13). The depth of the aperture should preferably be at least equal to the width of the bearing to be used, e.g. the depth of the aperture should be in the range 3-10 mm for a 3 mm wide bearing.

FIG. 8 shows a schematic diagram of the shaft 300 of FIG. 3 once the two pulleys 600, two bearings 801 and two belts 802 are mounted. The pulleys are constrained on the shaft by the flange 303 on one side and the bearing 801 on the other side. The pulleys cannot rotate freely on the shaft due to the co-operating features described above and shown in FIGS. 5 and 6. The belts are prevented from slipping off the pulleys by the flange 303 on one side and a raised edge 803 on the pulley on the other side.

The pulleys 600 mounted on the shaft 300 may be different according to the application. If the shaft is to be driven (i.e. by a drive shaft described below) the pulleys may have teeth (e.g. semi-circular teeth) if belts with teeth on the inside surface are used. If the belts used are smooth on both sides, or if the shaft is not to be driven, smooth surfaced pulleys may be used.

In the example shown, the pitch of the drive belts is 70 mm and the common shaft is 90 mm long. The diameter of the shaft is 6 mm, the diameter of the flange is 13 mm and the depth of the aperture is 8 mm.

In the arrangement shown in FIGS. 3-8, the common shaft is mounted in the dispenser unit using the bearings 801. These bearings are very close to the pulleys on which forces are exerted by the media being handled. This is beneficial as it reduces the stresses on the common shaft.

Although the diagrams above show the common shaft being used to mount pulleys for carrying belts, the shaft could be used to mount other pulleys, e.g. pulleys for handling media directly (e.g. pulleys 90 and 92 in FIG. 1). The shafts described above may be used in a number of places in an ATM including the pick and presenter modules.

Although the pulley-mounting region 304 is shown above as having raised features to prevent a pulley from rotating on the shaft, in an alternative embodiment, the pulley-mounting region could have a non-circular cross-section (e.g. polygonal cross-section) with the pulley having a corresponding polygonal central aperture. This would achieve the same effect of preventing the pulley from rotating freely on the shaft. In an alternative embodiment, the pulley-mounting region could have a substantially circular cross-section and the pulley could be allowed to rotate freely on the shaft. This design would be suitable for an idler pulley but not for a drive pulley.

Although the aperture 308 is shown above as having a substantially polygonal cross-section, the aperture could have any other suitable cross-section such that the same effect could be achieved, i.e. that rotation of a shaft inserted into the aperture 308 would cause rotation of the modular shaft 300 about the same axis of rotation. Other suitable cross-sections include a cruciform or elliptical cross-section.

Although the belt 802 is shown as being constrained between the flange and a raised edge on the pulley, alternate structures to the raised edge could be used, such as a washer-like element, of a similar outer diameter to the flange, which could be placed on to the shaft prior to the mounting of the bearing.

The common shaft 300 is integrally molded from polybutylene terephthalate (PBT) which is a thermoplastic polyester. This makes the shaft both simple to manufacture and low cost, whilst also being sufficiently durable. The shaft may therefore be considered to be a disposable item in some situations.

FIG. 9 shows a drive shaft 900 which can be used to drive the common shaft described above and shown in FIGS. 3-8. The drive shaft also comprises three sections: a connecting section 901, a central section 902 and an end section 903.

The connecting section 901, at one end of the drive shaft 900, is designed to be inserted into the aperture 308 in the end of the common shaft 300 (see FIGS. 3 and 7). The connecting section therefore has a polygonal cross-section that is substantially identical to the shape of the aperture, as shown in FIG. 10. As discussed above, the shape of the aperture need not be polygonal and therefore the cross-section of the connecting section could have an alternative shape to match that of the aperture. Preferably the connecting section 901 is of a size such that there is a tight push fit of the section into the aperture 308 in the end of the common shaft. The central section 902 has a cruciform cross-section and is similar to the central section 301 of the common shaft. The end section 903 is designed for mounting a gear (or gear wheel) which can be connected either directly or via a gearing mechanism to a motor to rotate the shaft. The end section 903 comprises a bearing mounting region with substantially circular cross-section (similar to the region 306 of the modular shaft 300), adjacent to the central section 902 and a shaped gear-mounting portion 905 adjacent to the end 906 of the drive shaft which is perpendicular to the longitudinal axis of the drive shaft 900. The shaped gear-mounting portion is shown in more detail in FIGS. 11 (side view) and 12 (cross-section, including gear). The gear-mounting portion 905 has a cruciform cross-section with a circular groove 1101 perpendicular to the longitudinal axis of the shaft and two raised features 1102 to prevent a gear 1201 mounted on the shaft from rotating freely. The central aperture in the gear 1202 has a circular ridge on it (not shown) which corresponds to the circular groove 1101 and enables the gear to be clicked into place on the drive shaft 900, as shown in FIG. 13. In the example shown, the drive shaft 900 is 78 mm long and the diameter of the end 906 is 8 mm.

The drive shaft 900 is also integrally molded from PBT and this offers the same benefits as described above in relation to the common shaft. Additionally, by using the same material for both the drive shaft 900 and the common shaft 300, problems due to material mismatch (e.g. due to differential wear, differential thermal expansion etc) are avoided.

FIG. 13 shows a drive shaft 900 coupled to a common shaft 300. The drive shaft is carrying a gear 1201 and a bearing 1301 and the connecting section 901 has been inserted into an aperture 308 in the common shaft. When the two shafts are coupled together, the bearing 801 around the aperture 308 into which the connecting section of the drive shaft has been inserted, serves to constrict the aperture in the common shaft and helps retain the drive shaft in the aperture in the modular shaft. As described above, the pulleys 600 may have teeth when they are drive pulleys. The gear 1201 is also a toothed wheel, however the teeth may be of a very different profile.

Although FIG. 13 shows the connection of a drive shaft to a single common shaft, further common shafts may be connected to the first common shaft if required (e.g. to enable one motor to drive two co-axial shafts). Connecting portions similar to the connecting portion 901 of the drive shaft may be used to connect two common shafts together.

Preferably a media dispenser unit in an ATM would comprise only one design of common shaft (and a fixed belt pitch) with any variations being in the length of the drive shaft used or the size of the pulleys or gears mounted on the shafts. This has the benefit that it reduces the numbers of piece parts and makes assembly and repair simpler. In addition to or instead of varying in length, the diameter of the end of the drive shaft may be varied (e.g. 1 5mm diameter) so that parts intended for use in different places (e.g. in the pick module or the presenter module) can be readily identified.

Any range or device value given herein may be extended or altered without losing the effect sought, as will be apparent to the skilled person.

The steps of the methods described herein may be carried out in any suitable order, or simultaneously where appropriate.

It will be understood that the above description of a preferred embodiment is given by way of example only and that various modifications may be made by those skilled in the art. 

1. A modular shaft assembly for a media dispenser comprising a common shaft and a drive shaft, wherein the common shaft comprises: a central portion between two end portions, each end portion comprising a pulley-mounting region and at least one end portion comprising an aperture in the end of the common shaft, co-axial to the common shaft, for receiving a connecting portion of the drive shaft, and wherein the drive shaft comprises: a central portion between a connecting portion and a drive portion, wherein the connecting portion is arranged to connect the drive shaft co-axially to the common shaft by insertion of the connecting portion into the aperture in an end portion of the common shaft, and the drive portion comprises a gear-mounting region.
 2. A modular shaft assembly as claimed in claim 1, wherein each end portion comprises an aperture in the end of the common shaft, co-axial to the common shaft, for receiving a connecting portion of the drive shaft.
 3. A modular shaft assembly as claimed in claim 1, wherein the central portions of the common shaft and the drive shaft have a cruciform cross-section.
 4. A modular shaft assembly as claimed in claim 1, wherein each end portion of the common shaft further comprises: a flange between the central portion and the pulley-mounting region; and a bearing-mounting region adjacent to the pulley-mounting region.
 5. A modular shaft assembly as claimed in claim 1, wherein the drive portion of the drive shaft further comprises: a bearing-mounting region between the gear-mounting region and the central portion.
 6. A modular shaft assembly as claimed in claim 1, wherein the apertures in the end portions of the common shaft and the connecting portion of the drive shaft have a polygonal cross-section.
 7. A modular shaft assembly as claimed in claim 6, wherein the apertures in the end portions of the common shaft and the connecting portion of the drive shaft have a hexagonal cross-section.
 8. A modular shaft assembly as claimed in claim 1, wherein each of the common shaft and the drive shaft are integrally molded.
 9. A modular shaft assembly as claimed in claim 8, wherein each of the common shaft and the drive shaft are integrally molded from thermoplastic polyester.
 10. A modular shaft assembly as claimed in claim 1, wherein the pulley-mounting regions of the common shaft comprise raised features arranged to prevent a pulley mounted on the shaft from rotating on the shaft.
 11. A modular shaft assembly as claimed in claim 1, wherein the common shaft is 90 mm long and has a diameter of 6 mm.
 12. A modular shaft assembly as claimed in claim 1, wherein the aperture is 3-15 mm deep.
 13. A media dispenser comprising a modular shaft assembly comprising a common shaft and a drive shaft, wherein the common shaft comprises: a central portion between two end portions, each end portion comprising a pulley-mounting region and at least one end portion comprising an aperture in the end of the common shaft, co-axial to the common shaft, for receiving a connecting portion of the drive shaft, and wherein the drive shaft comprises: a central portion between a connecting portion and a drive portion, wherein the connecting portion is arranged to connect the drive shaft co-axially to the common shaft by insertion of the connecting portion into the aperture in an end portion of the common shaft, and the drive portion comprises a gear-mounting region.
 14. A media dispenser as claimed in claim 13, further comprising one or more additional common shafts. 